若载波uC(t)=UCcosωCt，调制信号uΩ(t)=UΩcosΩt，则调相波的表达式为(). A: uPM(t)=UCcos(ωCt+mfsinΩt) B: uPM(t)=UCcos(ωCt+mpcosΩt) C: uPM(t)=UC(1+mpcosΩt)cosωCt D: uPM(t)=kUΩUCcosωCtcosΩt

若载波uC（t）=UCcosωCt，调制信号uΩ（t）=UΩcosΩt，则调相波的表达式为（）. A: uPM（t）=UCcos（ωCt＋mfsinΩt） B: uPM（t）=UCcos（ωCt＋mpcosΩt） C: uPM（t）=UC（1＋mpcosΩt）cosωCt D: uPM（t）=kUΩUCcosωCtcosΩt

若载波vc(t)=VCMcosωCt调制信号vΩ(t)=VΩMcosΩt，则调相波的表达式为()。 A: VPM(t)=VCMcos(ωCt+mfsinΩt) B: VPM(t)=VCMcos(ωCt+mpcosΩt) C: VPM(t)=VCM(1+mpcosΩt)cosωCt D: VPM(t)=kVΩMVCMcosΩtcosωCt

若载波uc(t)=Ucmcosωct,调制信号uΩ(t)= UΩmcosΩt，则调相波的表达式为 A: uFM(t)=Ucmcos（ωct＋mpcosΩt） B: uFM(t)=Ucmcos（ωct＋mfsinΩt） C: uFM(t)=Ucm（1＋mpcosΩt）cosωct D: uFM(t)=kUΩmUcmcosωctcosΩt

5．若载波uC(t)=UCcosωCt,调制信号uΩ(t)= UΩcosΩt，则调相波的表达式为 （ ） A: A．uPM(t)=UCcos（ωCt＋mfsinΩt） B: B．uPM(t)=UCcos（ωCt＋mpcosΩt） C: C．uPM(t)=UC（1＋mpcosΩt）cosωCt D: D．uPM(t)=kUΩUCcosωCtcosΩt

for i in range(b.max_row): for j in range(b.max_column): print(b.cell(row=i,column=j).value)上面语句运行的结果是：__________。 A: 1 1 1 1 1 1 1 1 1 1 B: 1111111111 C: 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 D: 出现异常

【单选题】CDMA通信的基站,假定基站A的码片序列是+1 +1 +1 -1 -1 +1 -1 -1,基站发射bit为101时,实际发射的信号是 A. +1 +1 +1 -1 -1 +1 -1 -1 +1 +1 +1 -1 -1 +1 -1 -1 –1 –1 –1 +1 +1 –1 +1 +1 B. +1 +1 +1 -1 -1 +1 -1 -1 –1 –1 –1 +1 +1 –1 +1 +1 +1 +1 +1 -1 -1 +1 -1 -1 C. +1 +1 +1 -1 -1 +1 -1 -1 +1 +1 +1 -1 -1 +1 -1 -1 +1 +1 +1 -1 -1 +1 -1 -1 D. –1 –1 –1 +1 +1 –1 +1 +1 –1 –1 –1 +1 +1 –1 +1 +1 –1 –1 –1 +1 +1 –1 +1 +1

for i in range(1,11): for j in range(1,11): b.cell(row=i,column=j).value=1 #b是一个工作表对象for i in range(1,11): for j in range(1,11): print(b.cell(row=i,column=j).value,end=" ") print()上面程序代码运行的结果是（）。 A: 1 B: 1 1 1 1 1 1 1 1 1 1 C: 1111111111 D: 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1

下列哪个码片序列不能用于CDMA通信 A: ( -1 -1 -1 +1 +1 -1 +1 +1 ) B: ( -1 -1 +1 -1 +1 +1 +1 -1 ) C: ( -1 +1 -1 +1 +1 -1 -1 -1 ) D: ( -1 +1 -1 -1 -1 -1 +1 -1 )

请仔细观察下面行列式的计算过程，如果四个等号都理解了，请选择A，否则请选择B。 | a 1 1 1 1 | |a＋4 a＋4 a＋4 a＋4 a＋4| | 1 a 1 1 1 | | 1 a 1 1 1 | | 1 1 a 1 1 |= | 1 1 a 1 1 | | 1 1 1 a 1 | | 1 1 1 a 1 | | 1 1 1 1 a | | 1 1 1 1 a | | 1 1 1 1 1 | | 1 a 1 1 1 | =(a＋4) | 1 1 a 1 1 | | 1 1 1 a 1 | | 1 1 1 1 a | | 1 1 1 1 1 | | 0 a–1 0 0 0 | =(a＋4) | 0 0 a–1 0 0 | | 0 0 0 a–1 0 | | 0 0 0 0 a–1 | =(a＋4)(a–1)^4